Folic acid: Why you need it before and during pregnancy

Why you need folic acid

If you’re pregnant or might become pregnant, it’s critically important to get enough folic acid, the synthetic form of vitamin B9, also known as folate.

Folic acid helps prevent neural tube defects (NTDs) – serious birth defects of the spinal cord (such as spina bifida) and the brain (such as anencephaly). The neural tube is the part of the embryo from which your baby’s spine and brain develop. NTDs affect about 3,000 pregnancies a year in the United States.

Neural tube defects occur at a very early stage of development, before many women even know they’re pregnant – which is why it’s important to begin taking folic acid before you start trying to conceive.

The Centers for Disease Control and Prevention (CDC) reports that women who take the recommended daily dose of folic acid starting at least one month before conception and during the first trimester of pregnancy reduce their baby’s risk of neural tube defects by up to 70 percent.

Some research suggests that folic acid may help lower your baby’s risk of other defects as well, such as cleft lip, cleft palate, and certain types of heart defects. It may also reduce your risk of preeclampsia, a serious blood pressure disorder that affects about 5 percent of pregnant women.

What else does folic acid do for you? Your body needs this nutrient to make normal red blood cells and prevent a type of anemia. It’s also essential for the production, repair, and functioning of DNA, our genetic map and a basic building block of cells. Getting enough folic acid is particularly important for the rapid cell growth of the placenta and your developing baby.

How much folic acid you need

To reduce your baby’s risk of developing a neural tube defect, experts recommend that you take 400 micrograms (mcg) of folic acid a day, beginning at least a month before you start trying to get pregnant.

In fact, because half of the pregnancies in the United States are unplanned, the CDC, the U.S. Public Health Service, the March of Dimes, the American College of Obstetricians and Gynecologists (ACOG), and other experts strongly recommend that all women of childbearing age get 400 mcg of folic acid every day.

Some groups, such as the U.S. National Institutes of Health, suggest boosting your intake to at least 600 mcg daily once you’re pregnant.

Check the label of your multivitamin supplement to be sure you’re getting enough. If you’re not, you can switch brands or take folic acid separately. (Never take more than one multivitamin a day.)

Don’t take more than 1,000 mcg per day of folic acid unless your healthcare provider advises you to. This is particularly important if you are a vegan. Vegans are at risk of being deficient in vitamin B12 and taking too much folic acid would make it hard to diagnose that deficiency.

When you might need extra folic acid

Women who are obese appear to be more likely to have a baby with a neural tube defect. If you’re significantly overweight, see your healthcare provider before you try to conceive. She may advise you to take more than 400 mcg of folic acid a day.

If you’ve previously been pregnant with a baby with a neural tube defect, you’ll probably be advised to take 4,000 mcg of folic acid a day. Be sure your current providers are aware of your history and schedule a visit before you try to get pregnant. With no intervention, women in this situation have a 3 to 5 percent chance of having another pregnancy complicated by an NTD.